1. Field of the Invention
The present invention is directed to the connection between a fluid supply cup and an adapter for a fluid applicator, more particularly to the connection between a paint cup and an adapter for a paint sprayer.
2. Description of the Related Art
Typically, the connection between a fluid supply and a fluid applicator, such as a paint sprayer for automobile painting and repainting in body shops, is via an adapter between the fluid supply and the sprayer, such as with a threaded connection between a supply cup and the adapter. However, it is difficult to prevent leaking from threading connections without precision machining of the threads or the use of seals, particularly for threaded connections that have short lengths. Also, it is difficult to quickly engage and disengage a threaded supply cup and an adapter.
Attempts have been made to create a connection between a supply cup and an adapter that can be engaged and disengaged quickly and easily. U.S. Published Applications US 2003/0006311 and US 2002/0134861 disclose a connection between the paint cup and the adapter with several parts, including a bayonet type connection. However, the connections in these applications are unnecessarily complex and do not solve the problem of sealing between the supply cup and the adapter.
What is needed is a connection between a fluid supply cup and an adapter that can be engaged and disengaged quickly and easily, and that provides a strong, tight seal around the connection.
In accordance with the present invention, a cover-connector is provided for covering a fluid supply container and connecting the container to a conduit, wherein one of the container and the conduit has a male frustoconical connecting surface and the other one of the container and the conduit has a threaded connecting surface. The novel cover-connector comprises a conduit side with a conduit connecting region, a container side with a container connecting region, and a passageway between the connecting regions, wherein one of the connecting regions has a female frustoconical surface having an acute frustoconical angle complementary to the male frustoconical connecting surface for frictional connection therebetween, and wherein the other one of the connecting regions has a threaded portion complementary to the threaded connecting surface for threaded connecting therebetween.
In one embodiment, a novel cover-connector for covering and connecting a paint container to a male tapered hollow bore adapter for use with a paint sprayer includes a generally frustoconical cover having an axis and extending from a vertex region to an edge at an obtuse frustoconical angle facing toward the paint container when covering the paint container, a container connecting region with threads adjoining the cover edge and extending toward the paint container when covering the paint container, the threads being normal to the axis, a generally frustoconical female fitting integrally connected to the cover at the vertex region, the fitting extending from the cover generally axially opposite from the container connecting region for receiving the male tapered hollow bore adapter, the fitting being angled to open axially and radially outwardly at an acute angle from the axis to a distal fitting end generally defining a plane normal to the axis, the fitting being complementary to the adapter while providing for frictional engagement therebetween, a passageway between the container connecting region and the fitting, and a generally cylindrical support wall extending axially from the cover edge to a distal wall end in the plane, whereupon engagement of the threads with the paint container and the fitting with the adapter provides fluid communication between the paint container and the adapter.
Also in accordance with the present invention, a fluid supply assembly for use with a fluid applicator comprises a fluid container and a conduit, wherein one of the container and the conduit has a male frustoconical connecting surface and the other one of the cover and the conduit has a threaded connecting surface, and a cover-connector for covering the container and connecting the container to the conduit, the cover-connector including a conduit side with a conduit connecting region, a container side with a container connecting region, and a passageway between the connecting regions, wherein one of the connecting regions has a female frustoconical surface having an acute frustoconical angle complementary to the male frustoconical connecting surface for frictional connection therebetween and wherein the other one of the connecting regions has a threaded portion complementary to the threaded connecting surface for threaded connection therebetween.
Also in accordance with the present invention, a novel method of connecting a fluid container to a fluid applicator comprises the steps of providing a conduit in fluid communication with the fluid applicator, providing the container, wherein one of the container and the conduit has a male frustoconical connecting surface and the other one of the container and the conduit has a threaded connecting surface, providing a cover-connector having a conduit side with a conduit connecting region, a container side with a container connecting region, and a passageway between the connecting regions, wherein one of the connecting regions has a female frustoconical surface having an acute frustoconical angle complementary to the male frustoconical connecting surface, and wherein the other of the connecting regions has a threaded portion complementary to the threaded connecting surface, threadingly connecting the threaded portion and the threaded connecting surface, and engaging the male frustoconical connecting surface with the female frustoconical surface and rotating the male frustoconical connecting surface and the female frustoconical surface with respect to one another, for frictional connection therebetween.